What has to be on a customer invoice for it to work as a business record, and how should I number and issue invoices?

What the invoice does in your books

An invoice is a document submitted to a customer that identifies a transaction for which the customer owes payment to the issuer. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: sellers issuing invoices to customers)

“An invoice is a document submitted to a customer, identifying a transaction for which the customer owes payment to the issuer.”

The seller uses the invoice as a source document to prove that sales transactions have been created. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: sellers issuing invoices)

“Another user is the seller, which uses the invoice as a source document to prove that sales transactions have been created.”

The total of all invoices issued, less any credit memos, will sum to the seller's credit sales total for the reporting period. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: sellers reporting credit sales for a reporting period, conditions: credit sales only; credit memos deducted)

“The total of all invoices issued, less any credit memos , will sum to the credit sales total for the seller’s reporting period.”

A source document captures the key information about a transaction, such as (open list) the names of the parties involved, amounts paid if any, the date, and the substance of the transaction. (jurisdiction: United States, entity_scope: businesses generally (no entity type stated), conditions: list is illustrative ('such as'), not exhaustive; amounts paid stated as '(if any)')

“A source document captures the key information about a transaction, such as the names of the parties involved, amounts paid (if any), the date, and the substance of the transaction.”

Partly established. Established: the invoice stands as the record supporting both (S02). Missing: the invoice originates the receivable; the invoice originates the revenue entry.

Required authority: authoritative professional or accounting standard. Highest achieved: high quality professional secondary reference.

The elements a customer invoice has to carry

See An invoice is a document submitted to a customer that identifies a transaction for which the customer owes payment to the issuer.

See The seller uses the invoice as a source document to prove that sales transactions have been created.

See A source document captures the key information about a transaction, such as (open list) the names of the parties involved, amounts paid if any, the date, and the substance of the transaction.

The article presents the items that follow as information an invoice typically identifies — a description of typical content, not a stated requirement and not stated to be exhaustive. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: invoices generally, conditions: hedged with 'typically')

“An invoice typically identifies the following information:”

Individual sales invoices should generally include, among other things, the date, the customer's name and address, the shipping address, the type of product, quantity sold, sales price, any shipping charges, and the amount of tax — the amount of tax thus appearing as its own item alongside the sales price and shipping charges. (jurisdiction: California, United States (California sales and use tax), entity_scope: Businesses issuing individual sales invoices for California sales and use tax purposes, conditions: Hedged: "should generally", not an absolute requirement; Qualified by the document's statement that required detail varies by industry; Publication 116, revision September 2018)

“Individual sales invoices should generally include the date, customer’s name and address, shipping address, type of product, quantity sold, sales price, any shipping charges, and the amount of tax.”

Not established from an authoritative source.

Required authority: authoritative professional or accounting standard. Highest achieved: high quality professional secondary reference, primary regulator or government.

Who the invoice identifies: you, your customer, the date and the number

See The article presents the items that follow as information an invoice typically identifies — a description of typical content, not a stated requirement and not stated to be exhaustive.

See Individual sales invoices should generally include, among other things, the date, the customer's name and address, the shipping address, the type of product, quantity sold, sales price, any shipping charges, and the amount of tax — the amount of tax thus appearing as its own item alongside the sales price and shipping charges.

The invoice number is listed among the information an invoice typically identifies. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: invoices generally, conditions: governed by the lead-in 'An invoice typically identifies the following information:'; the article does not state the number must be unique)

“The invoice number”

The name and address of the seller are listed among the information an invoice typically identifies. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: invoices generally, conditions: governed by the lead-in 'An invoice typically identifies the following information:')

“The name and address of the seller”

The name and address of the buyer are listed among the information an invoice typically identifies. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: invoices generally, conditions: governed by the lead-in 'An invoice typically identifies the following information:')

“The name and address of the buyer”

Not established from an authoritative source.

Required authority: authoritative professional or accounting standard, primary regulator or government. Highest achieved: high quality professional secondary reference, primary regulator or government.

What is being billed: description, quantities, amounts and the date of delivery

See The article presents the items that follow as information an invoice typically identifies — a description of typical content, not a stated requirement and not stated to be exhaustive.

See Individual sales invoices should generally include, among other things, the date, the customer's name and address, the shipping address, the type of product, quantity sold, sales price, any shipping charges, and the amount of tax — the amount of tax thus appearing as its own item alongside the sales price and shipping charges.

The date of shipment, or the date when services were delivered, is listed among the information an invoice typically identifies. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: invoices generally, conditions: governed by the lead-in 'An invoice typically identifies the following information:')

“The date of shipment or when services were delivered”

A description of the items purchased is listed among the information an invoice typically identifies. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: invoices generally, conditions: governed by the lead-in 'An invoice typically identifies the following information:')

“A description of the items purchased”

The quantities and total costs of the items purchased are listed among the information an invoice typically identifies. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: invoices generally, conditions: governed by the lead-in 'An invoice typically identifies the following information:'; the article does not mention unit rates or currency)

“The quantities and total costs of the items purchased”

Partly established. Established: what is being billed (S11); the period or delivery date the charge relates to (S10). Missing: the quantities and rates or the basis on which the charge is computed; the currency of the amounts.

Required authority: authoritative professional or accounting standard. Highest achieved: high quality professional secondary reference, primary regulator or government.

Payment terms: the due date and how the customer can pay

The invoice due date is defined as the date on which the seller expects to receive payment from the buyer. (jurisdiction: United States (US-based professional publisher; the article states no other jurisdiction and describes general commercial billing terminology), entity_scope: sellers and buyers exchanging invoices)

“The invoice due date is the date on which a seller expects to receive payment from a buyer.”

To arrive at the due date, the customer must find the invoice date and the payment terms on the invoice and calculate the due date from those two items; the article notes the invoice date could sit in one of several spots and the payment terms may not be next to it. (jurisdiction: United States (US-based professional publisher; the article states no other jurisdiction), entity_scope: customers calculating a due date from a received invoice, conditions: applies where the invoice shows an invoice date and payment terms rather than a stated due date)

“The customer must locate the invoice date (which could be located in one of several spots on the invoice), as well as the payment terms (which may not be located adjacent to the invoice date), and then calculate the due date based on these two items of information.”

As a best practice, the invoice should state the exact date on which payment is due, in bold large font and in its own box in a prominent position, which the author says makes it much less likely the customer will fail to enter the due date in accounts payable software. (jurisdiction: United States (US-based professional publisher; the article states no other jurisdiction), entity_scope: sellers issuing invoices, conditions: recommended best practice, not a requirement)

“Clearly state the due date . To remedy any uncertainty about the invoice due date, state the exact date on which payment is due on the invoice, in bold large font, and in its own box in a prominent location on the page. Doing so makes it much less likely that the customer will ignore entering the due date in the accounts payable software.”

Some invoices carry a 'pay now' option that lets customers use a variety of payment types to pay immediately. (jurisdiction: United States (US accounting reference publisher; the article states no jurisdictional limit of its own), entity_scope: some invoices, conditions: hedged with 'some invoices')

“Some invoices come with a “pay now” option, allowing customers to use a variety of payment types to make an immediate payment.”

Not established from an authoritative source.

Required authority: authoritative professional or accounting standard. Highest achieved: high quality professional secondary reference.

What the invoice must show when you charge sales tax

See Individual sales invoices should generally include, among other things, the date, the customer's name and address, the shipping address, the type of product, quantity sold, sales price, any shipping charges, and the amount of tax — the amount of tax thus appearing as its own item alongside the sales price and shipping charges.

The vendor must always state the amount of sales tax due separately on the invoice or receipt given to the customer. (jurisdiction: New York State, United States, entity_scope: registered New York State sales tax vendors issuing an invoice or receipt to a customer, effective_from: 2011-06-02)

“You must always separately state the amount of sales tax due on the invoice or receipt that you give your customer.”

A vendor selling both taxable and nontaxable goods or services must identify on the invoice or receipt which of the items sold are subject to sales tax and which are not. (jurisdiction: New York State, United States, entity_scope: registered New York State sales tax vendors selling both taxable and nontaxable goods or services, effective_from: 2011-06-02, conditions: applies where the vendor sells both taxable and nontaxable goods or services)

“If you sell both taxable and nontaxable goods or services, you must identify which of the items you sell are subject to sales tax and which are not on the invoice or receipt.”

Whatever the industry, the records must let CDTFA determine the date of the sale, what was sold, all taxable and nontaxable charges, and how much tax was applied to the sale. (jurisdiction: California, United States (California sales and use tax), entity_scope: Businesses required to keep California sales and use tax records, conditions: Publication 116, revision September 2018; Stated as what CDTFA must be able to determine from the records, not as a prescribed invoice layout)

“In any case, the CDTFA must be able to determine the date of the sale, what you sold, all taxable and nontaxable charges, and how much tax was applied to the sale.”

Partly established. Established: presentation of the tax separately from the amount charged (S17). Missing: the elements an invoice is required to show where the business charges sales tax; identification of the seller.

Showing the tax separately from the amount it is charged on

See Individual sales invoices should generally include, among other things, the date, the customer's name and address, the shipping address, the type of product, quantity sold, sales price, any shipping charges, and the amount of tax — the amount of tax thus appearing as its own item alongside the sales price and shipping charges.

See The vendor must always state the amount of sales tax due separately on the invoice or receipt given to the customer.

See A vendor selling both taxable and nontaxable goods or services must identify on the invoice or receipt which of the items sold are subject to sales tax and which are not.

See Whatever the industry, the records must let CDTFA determine the date of the sale, what was sold, all taxable and nontaxable charges, and how much tax was applied to the sale.

What your invoice numbering has to achieve

Source documents are frequently (not always) identified with a unique number, the stated purpose being that they can be differentiated in the accounting system. (jurisdiction: United States, entity_scope: businesses generally (no entity type stated), conditions: stated as common practice ('frequently'), not as a requirement)

“Source documents are frequently identified with a unique number, so that they can be differentiated in the accounting system .”

Pre-numbering documents is described as particularly useful because it allows a company to investigate whether any documents are missing. (jurisdiction: United States, entity_scope: companies generally (no entity type stated), conditions: stated as a benefit ('particularly useful'), not as a requirement)

“The pre-numbering of documents is particularly useful, since it allows a company to investigate whether any documents are missing.”

Tracing starts with a source document and follows it forward into the accounting records, and it tests completeness. (jurisdiction: United States, entity_scope: audit/testing of accounting records generally)

“Tracing starts with a source document and follows it forward into the accounting records to test completeness.”

Not established from an authoritative source.

Required authority: authoritative professional or accounting standard. Highest achieved: high quality professional secondary reference, primary regulator or government.

Unique numbers, visible gaps, and tracing a payment back to the document

See Source documents are frequently (not always) identified with a unique number, the stated purpose being that they can be differentiated in the accounting system.

See Pre-numbering documents is described as particularly useful because it allows a company to investigate whether any documents are missing.

See Tracing starts with a source document and follows it forward into the accounting records, and it tests completeness.

The records must provide the opportunity to trace any transaction back to the original source or forward to a final total. (jurisdiction: New York State, United States, entity_scope: registered New York State sales tax vendors who use a point-of-sale system, effective_from: 2011-06-02, conditions: applies only where the business uses a POS system)

“The records must provide the opportunity to trace any transaction back to the original source or forward to a final total.”

Partly established. Established: an order in which a missing document is visible (S21). Missing: every issued invoice uniquely identified; traceability from a payment or a ledger entry back to the document.

Required authority: authoritative professional or accounting standard. Highest achieved: high quality professional secondary reference, primary regulator or government.

Numbering shapes: prefixes, year series and per-transaction-type series

The auto-generated Zoho Books invoice number has an editable Prefix component that can be set for the new financial year's sequence; the page gives changing INV23-xxxx to INV24-xxxx as an example of such a change. (jurisdiction: United States (Zoho Books US edition help, US-EN), entity_scope: Zoho Books US organisations using auto-generated invoice numbers, platform: Zoho Books, platform_edition: US edition (US-EN) help, as fetched 2026-09-08, conditions: INV23-xxxx to INV24-xxxx is given only as an instance, not as a required format)

“In the next pop-up, edit the Prefix of the invoice number based on the new financial year’s sequence. For instance, you can change the prefix from INV23-xxxx to INV24-xxxx”

After saving a changed prefix in Zoho Books, invoice numbers for the user's future invoices are automatically generated with the new prefix. (jurisdiction: United States (Zoho Books US edition help, US-EN), entity_scope: Zoho Books US organisations using auto-generated invoice numbers, platform: Zoho Books, platform_edition: US edition (US-EN) help, as fetched 2026-09-08, conditions: applies to future invoices; the page says nothing about invoices already issued)

“The invoice numbers for your future invoices will be automatically generated with the new prefix.”

QuickBooks Online offers a Custom transaction numbers option that lets the user set their own numbering preference for invoices, sales receipts and credit memos; turning it on adds a number field in which the user can enter any number or letter format they want. (jurisdiction: United States (en-US QuickBooks Online help article, US support and sales contacts), entity_scope: QuickBooks Online company files / subscribers listed for this article (Advanced, Plus, Simple Start, Essentials, Lite, Free, Intuit Enterprise Suite, QuickBooks Solopreneur Plus), platform: QuickBooks Online, platform_edition: US (en-US) edition, article updated 8/28/2026, effective_from: 2026-08-28, conditions: applies when the Custom transaction numbers option is used)

“Use the Custom transaction numbers option to set your own numbering preference for invoices, sales receipts, and credit memos. This adds a number field where you can enter any number or letter format you want.”

Not established from an authoritative source.

Required authority: authoritative professional or accounting standard. Highest achieved: official platform documentation.

Who assigns the number, and keeping control of it

See QuickBooks Online offers a Custom transaction numbers option that lets the user set their own numbering preference for invoices, sales receipts and credit memos; turning it on adds a number field in which the user can enter any number or letter format they want.

To use one's own sales transaction numbers in QuickBooks Online, the Custom transaction numbers setting has to be turned on in the company settings. (jurisdiction: United States (en-US QuickBooks Online help article), entity_scope: QuickBooks Online company files covered by this article, platform: QuickBooks Online, platform_edition: US (en-US) edition, article updated 8/28/2026, effective_from: 2026-08-28, conditions: only where the user wants to use their own sales transaction numbers)

“If you want to use your own sales transaction numbers, make sure Custom transaction numbers is on in your company settings.”

In QuickBooks Online, invoices, sales receipts and credit memos share one custom transaction number list, and the last number the user enters becomes the next number on all three of those sales forms. (jurisdiction: United States (en-US QuickBooks Online help article), entity_scope: QuickBooks Online company files covered by this article; invoices, sales receipts and credit memos, platform: QuickBooks Online, platform_edition: US (en-US) edition, article updated 8/28/2026, effective_from: 2026-08-28, conditions: custom transaction numbering in use)

“Invoices, sales receipts, and credit memos share the same custom transaction number list. The last number you enter becomes the next number on all three sales forms.”

An invoice's number is changed by the user typing the custom number or letter sequence they want into the Invoice no. field on the invoice. (jurisdiction: United States (en-US QuickBooks Online help article), entity_scope: QuickBooks Online company files covered by this article, platform: QuickBooks Online, platform_edition: US (en-US) edition, article updated 8/28/2026, effective_from: 2026-08-28, conditions: custom transaction numbers turned on; as part of the documented procedure to change an invoice number)

“In the Invoice no. field, enter the custom number or letter sequence you want to use.”

Zoho Books auto-generates invoice numbers, and the page states the user can modify the auto-generated invoice number for a new financial year in two ways. (jurisdiction: United States (Zoho Books US edition help, US-EN), entity_scope: Zoho Books US organisations using auto-generated invoice numbers, platform: Zoho Books, platform_edition: US edition (US-EN) help, Year End Accounting topic, as fetched 2026-09-08, conditions: the two ways named by the page are the invoice creation page and the Transaction Number Series page)

“You can modify the auto-generated invoice number according to the new financial year in two ways:”

Partly established. Established: who assigns numbers (S27, S30, S31). Missing: how the scheme holds when several people, sites or systems issue invoices; what has to be planned when the business moves to a different accounting system mid-sequence.

Required authority: authoritative professional or accounting standard, official platform documentation. Highest achieved: official platform documentation.

How accounting software assigns and preserves invoice numbers, and what void or delete does

See In QuickBooks Online, invoices, sales receipts and credit memos share one custom transaction number list, and the last number the user enters becomes the next number on all three of those sales forms.

See Zoho Books auto-generates invoice numbers, and the page states the user can modify the auto-generated invoice number for a new financial year in two ways.

In QuickBooks Online, voiding a transaction keeps a record of that transaction in the books, and that retained record does not affect totals. (jurisdiction: United States (en-US QuickBooks Online help edition), entity_scope: Businesses using QuickBooks Online, platform: QuickBooks Online, platform_edition: QuickBooks Online Advanced, Plus, Simple Start, Essentials, Free, Lite, Intuit Enterprise Suite, QuickBooks Solopreneur Plus, effective_from: 2026-09-07 (article last updated))

“When you void a transaction, you keep a record of the transaction in your books that don’t affect your totals.”

In QuickBooks Online, a voided transaction is set to zero and is displayed as void in the user's records. (jurisdiction: United States (en-US QuickBooks Online help edition), entity_scope: Businesses using QuickBooks Online, platform: QuickBooks Online, platform_edition: QuickBooks Online Advanced, Plus, Simple Start, Essentials, Free, Lite, Intuit Enterprise Suite, QuickBooks Solopreneur Plus, effective_from: 2026-09-07 (article last updated))

“Voided transactions are zero and show as void in your records.”

In QuickBooks Online, when a transaction is deleted the transaction number does not change. (jurisdiction: United States (en-US QuickBooks Online help edition), entity_scope: Businesses using QuickBooks Online, platform: QuickBooks Online, platform_edition: QuickBooks Online Advanced, Plus, Simple Start, Essentials, Free, Lite, Intuit Enterprise Suite, QuickBooks Solopreneur Plus, effective_from: 2026-09-07 (article last updated), conditions: stated in the context of deleting a transaction)

“You remove a transaction everywhere except the audit log when you delete it. The transaction number doesn't change.”

Partly established. Established: how accounting software assigns invoice numbers (S25, S27, S28, S29, S30, S31); how accounting software preserves invoice numbers (S34). Missing: how accounting software enforces invoice numbers; what accounting software does to the number and the record when an invoice is voided, deleted or re-issued.

When an invoice counts as issued, and the copy you keep

The billing procedure set out in this article addresses three tasks: collecting the information needed to construct an invoice, creating invoices, and issuing them to customers; issuing to the customer is described as a distinct task from creating the invoice. (jurisdiction: United States (implied by the US publisher AccountingTools, Inc. and the article's reference to customer sales-tax codes; the document itself states no jurisdiction), entity_scope: Businesses following the billing procedure described in this article, conditions: applies to the billing procedure as described in this article)

“The following billing procedure addresses three tasks in the billing process, which involve collecting the information needed to construct an invoice , creating invoices, and issuing them to customers .”

Where invoices are produced in multiple copies, the procedure says to separate (burst) the copies and keep the copies designated for retention by the business. (jurisdiction: United States (implied by the US publisher AccountingTools, Inc. and the article's reference to customer sales-tax codes; the document itself states no jurisdiction), entity_scope: Businesses producing multi-copy paper invoices, conditions: only if the invoices are in multiple copies)

“If the invoices are in multiple copies, burst the copies and retain the designated copies.”

In this procedure the last act of the billing clerk in sending a paper invoice is handing the billing envelopes to the mail room for mailing; delivery to the customer is by post. (jurisdiction: United States (implied by the US publisher AccountingTools, Inc. and the article's reference to customer sales-tax codes; the document itself states no jurisdiction), entity_scope: Businesses with a mail room that mail paper invoices, conditions: paper invoicing via internal mail room)

“Deliver the billing envelopes to the mail room for mailing.”

The retained copies of issued invoices are filed, as needed, in one of two filing orders the article names: by invoice number or by customer name. (jurisdiction: United States (implied by the US publisher AccountingTools, Inc. and the article's reference to customer sales-tax codes; the document itself states no jurisdiction), entity_scope: Businesses retaining paper copies of issued invoices, conditions: filing done "as needed"; applies to the copies retained under Step 3)

“File the retained invoice copies as needed, either by invoice number or by customer name.”

Partly established. Established: what record of issue a business is expected to keep (S36). Missing: what constitutes issue or delivery of an invoice.

Delivering the invoice and recording the issue

See The billing procedure set out in this article addresses three tasks: collecting the information needed to construct an invoice, creating invoices, and issuing them to customers; issuing to the customer is described as a distinct task from creating the invoice.

See In this procedure the last act of the billing clerk in sending a paper invoice is handing the billing envelopes to the mail room for mailing; delivery to the customer is by post.

In the procedure described, the copy of the invoice designated for the customer is the one placed into an envelope for sending, distinguishing the customer's copy from the copies retained internally. (jurisdiction: United States (implied by the US publisher AccountingTools, Inc. and the article's reference to customer sales-tax codes; the document itself states no jurisdiction), entity_scope: Businesses sending paper invoices to customers by mail, conditions: paper invoicing)

“Stuff the invoice version designated for customers into envelopes.”

The article recommends moving from paper invoices to electronic invoices, on the stated basis that electronic delivery is faster and can be tracked. (jurisdiction: United States (implied by the US publisher AccountingTools, Inc.; the document itself states no jurisdiction), entity_scope: Businesses currently issuing paper invoices, conditions: presented as a best practice, not a requirement)

“In addition, transition from paper to electronic invoices for faster delivery and tracking.”

Partly established. Established: how the invoice is delivered (S37, S39). Missing: at what point it is treated as issued; what record of the issue — to whom, on what date, in what form — the business keeps.

Correcting or cancelling an invoice you have already issued

A credit memo (credit memorandum) is a document the seller of goods or services issues to the buyer that reduces the amount the buyer owes the seller under an earlier invoice. (jurisdiction: Not stated in the document; general commercial practice described by a US-based publisher (AccountingTools, Inc.), entity_scope: Sellers of goods or services and their buyers, conditions: presupposes an earlier invoice)

“A credit memo is a contraction of the term "credit memorandum," which is a document issued by the seller of goods or services to the buyer, reducing the amount that the buyer owes to the seller under the terms of an earlier invoice .”

A credit memo may also be issued to correct billing errors on an invoice, such as overcharges or incorrect quantities (examples, not a closed list). (jurisdiction: Not stated in the document; general commercial practice described by a US-based publisher (AccountingTools, Inc.), entity_scope: Sellers correcting their own issued invoices, conditions: a billing error exists on an already-issued invoice)

“It may also be issued to correct billing errors, such as overcharges or incorrect quantities on an invoice.”

Partly established. Established: the expected treatment of an already-issued invoice that must be corrected (S42). Missing: the expected treatment of an already-issued invoice that must be cancelled; the record of the original issue is preserved.

Required authority: authoritative professional or accounting standard. Highest achieved: high quality professional secondary reference, official platform documentation, primary regulator or government.

Credit memos and voiding: fixing an invoice without deleting it

See In QuickBooks Online, voiding a transaction keeps a record of that transaction in the books, and that retained record does not affect totals.

See In QuickBooks Online, when a transaction is deleted the transaction number does not change.

See A credit memo (credit memorandum) is a document the seller of goods or services issues to the buyer that reduces the amount the buyer owes the seller under an earlier invoice.

See A credit memo may also be issued to correct billing errors on an invoice, such as overcharges or incorrect quantities (examples, not a closed list).

Partly established. Established: how an already-issued invoice is corrected without being deleted (S42); how an already-issued invoice is cancelled without being deleted (S32, S33). Missing: how the numbered set stays complete and explainable afterwards.

Required authority: authoritative professional or accounting standard, official platform documentation. Highest achieved: high quality professional secondary reference, official platform documentation.

How long issued invoices must be kept, and in what form

A vendor must retain a true copy of each sales slip, invoice, receipt, contract, statement or other memorandum of sale; each guest check, hotel guest check, receipt from admissions such as ticket stubs and receipt from dues; and each cash register tape and any other original sales document. (jurisdiction: New York State, United States, entity_scope: registered New York State sales tax vendors, effective_from: 2011-06-02)

“You must retain a true copy of each: sales slip, invoice, receipt, contract, statement, or other memorandum of sale; guest check, hotel guest check, receipt from admissions such as ticket stubs, receipt from dues; and cash register tape and any other original sales document.”

A vendor must keep all of its records for a minimum of three years from the due date of the return to which those records relate, or from the date the return is filed if that is later. (jurisdiction: New York State, United States, entity_scope: registered New York State sales tax vendors, effective_from: 2011-06-02)

“You must keep all of your records for a minimum of three years from the due date of the return to which those records relate, or the date the return is filed, if later.”

The Tax Department may require a vendor to keep records for longer than the minimum period, such as where the records are the subject of an audit, court case or other proceeding. (jurisdiction: New York State, United States, entity_scope: registered New York State sales tax vendors, effective_from: 2011-06-02, conditions: examples given are not an exhaustive list of when a longer period may be required)

“The Tax Department may require you to keep records for a longer period of time, such as when the records are the subject of an audit, court case, or other proceeding.”

Records maintained in an electronic format must be made available to the Tax Department in an electronically readable form. (jurisdiction: New York State, United States, entity_scope: registered New York State sales tax vendors maintaining records in electronic format, effective_from: 2011-06-02, conditions: applies where records are maintained in an electronic format)

“Records that are maintained in an electronic format must be made available to the Tax Department in an electronically readable form.”

The issued invoice and the entry it supports

See Tracing starts with a source document and follows it forward into the accounting records, and it tests completeness.

Vouching starts with a recorded transaction and works backward to the source document, and it tests existence, occurrence, or validity. (jurisdiction: United States, entity_scope: audit/testing of accounting records generally)

“Vouching starts with a recorded transaction and works backward to the source document to test existence, occurrence, or validity.”

Source documents are critical to auditors, who use them as evidence that recorded transactions actually occurred. (jurisdiction: United States, entity_scope: auditors of businesses generally)

“Source documents are critical to auditors , who use them as evidence that recorded transactions actually occurred.”

To be considered complete, electronic records must permit direct reconciliation of receipts, invoices and other source documents with the entries in the taxpayer's books and records and on its returns. (jurisdiction: New York State, United States, entity_scope: registered New York State sales tax vendors whose business uses a point-of-sale system and keeps electronic records, effective_from: 2011-06-02, conditions: applies only where the business uses a POS system)

“In order to be considered complete, the electronic records must permit the direct reconciliation of the receipts, invoices, and other source documents with the entries in the books and records and on the returns of a taxpayer.”

Not established from an authoritative source.

Required authority: authoritative professional or accounting standard. Highest achieved: high quality professional secondary reference, primary regulator or government.

Keeping the invoice usable as evidence later

See The records must provide the opportunity to trace any transaction back to the original source or forward to a final total.

See Source documents are critical to auditors, who use them as evidence that recorded transactions actually occurred.

Once a source document's information has been recorded in the accounting system, the source document is indexed for easy access and archived. (jurisdiction: United States, entity_scope: businesses generally (no entity type stated), conditions: applies after the information has been recorded in the accounting system)

“Once the information in a source document has been recorded in the accounting system, the source document is indexed for easy access and archived.”

Digital records are widely accepted for accounting and auditing purposes, provided they are accurate, complete and securely stored. (jurisdiction: United States, entity_scope: businesses generally (no entity type stated), conditions: acceptance hedged as 'widely accepted', not universal; conditioned on the records being accurate, complete and securely stored)

“Digital records are widely accepted for accounting and auditing purposes, provided they are accurate, complete, and securely stored.”

It is usually (not invariably) necessary to retain source documents for several years; no specific period is stated. (jurisdiction: United States, entity_scope: businesses generally (no entity type stated), conditions: hedged ('usually necessary'); duration stated only as 'several years')

“It is usually necessary to retain source documents for several years.”

Partly established. Established: keeping the copy as issued (S43); how long issued invoices remain available (S44). Missing: its agreement with the ledger entry it supports.

Required authority: authoritative professional or accounting standard, primary regulator or government. Highest achieved: high quality professional secondary reference, primary regulator or government.